Bug #74451 [Fbk->NoF]: Sine values exceed 1

Edit report at https://bugs.php.net/bug.php?id=74451&edit=1 ID: 74451 Updated by: php-bugs@lists.php.net Reported by: m_sun at mail dot ru Summary: Sine values exceed 1 -Status: Feedback +Status: No Feedback Type: Bug Package: Math related Operating System: Alpine Linux PHP Version: 5.6.30 Private report: N New Comment: No feedback was provided. The bug is being suspended because we assume that you are no longer experiencing the problem. If this is not the case and you are able to provide the information that was requested earlier, please do so and change the status of the bug back to "Re-Opened". Thank you. Previous Comments: ------------------------------------------------------------------------ [2017-04-16 22:18:19] m_sun at mail dot ru PS: Seems like this is not a hardware issue, neither musl libc. Result is always the same even after restarting php5-fpm. Alpine Linux uses grsec patch and loads binaries in arbitrary memory addresses on each start. I additionally posted a bug report on Alpine Linux board. ------------------------------------------------------------------------ [2017-04-16 22:07:25] m_sun at mail dot ru Standard libc sin() works just fine. Bc also gives correct result on the machine in question: echo 's(60)' | bc -l But problem with php is still there: php5 -r 'echo sin(60) . "\n";' output is 19880855899899 Right now I use a workaround echo sin(fmod(60, M_PI * 2)); ------------------------------------------------------------------------ [2017-04-16 18:21:53] requinix@php.net Does a simple #include <math.h> #include <stdio.h> void main(void) { printf("%f\n", sin(60.0)); } work correctly? ------------------------------------------------------------------------ [2017-04-16 11:16:53] m_sun at mail dot ru You are right: the problem can't be reproduced in a testbed for PHP 5.6.30. I suppose there is a problem in realization (librariess are compiled against musl libc on Alpine Linux) or a hardware issue... Thank you danack at php dot com <?php $start = 60.0; $a = $start; $da = 0.1; $target = M_PI + $start; $tab = array(); while ($a < $target) { $item['rad'] = $a; $item['deg'] = number_format(rad2deg($a), 2); $item['sin'] = sin($a); $item['cos'] = cos($a); $tab[] = $item; $a += $da; } ?> <style> table, td, th { border-collapse:collapse; border:1px solid #000; } </style> <table> <tr> <th>Radian</th> <th>Degrees</th> <th>Sin</th> <th>Cos</th> </tr> <?php foreach($tab as $item): ?> <tr> <td><?= $item['rad'] ?></td> <td><?= $item['deg'] ?></td> <td><?= $item['sin'] ?></td> <td><?= $item['cos'] ?></td> </tr> <?php endforeach; ?> </table> ------------------------------------------------------------------------ [2017-04-16 10:17:18] danack@php.net I can't reproduce what you're reporting: https://3v4l.org/fnd5R Please can you provide an actual runnable reproduce script. ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=74451 -- Edit this bug report at https://bugs.php.net/bug.php?id=74451&edit=1